1. Field of the Invention
The present invention relates generally to an apparatus and method for enhancing the readability of a character in a mobile terminal, and more particularly, to an apparatus and method for enhancing visibility while minimizing current consumption, when a user views the character on a screen of a mobile terminal.
2. Description of the Related Art
As the utilization of a slide out keyboard and/or touch screen display in a mobile terminal has increased, the screen size of the mobile terminal has also increased, and a display included in the mobile terminal is continually developing. More specifically, displays having excellent color reproduction ranges and contrast ratios are currently being developed and adopted, such as a Liquid Crystal Display (LCD) displays and an Active Matrix Organic Light-Emitting Diode (AMOLED) displays.
In a mobile terminal, because current consumption is a very important factor, a low-power driving is important. However, an LCD includes a backlight, and has constant current consumption at all times. That is, regardless of whether the lightness of a displayed image is high or low, current consumption is constant. In contrast, an AMOLED consumes different amounts of current depending on pixels of an input image. For example, the AMOLED has low current consumption when a dark image is displayed, and has high current consumption when a bright image is displayed. Further, when a bright image is displayed, there is a tendency that current consumption by an AMOLED is significantly higher than the current consumption by an LCD for the same image.
Accordingly, consumption and visibility are important factors that must be taken into consideration in displaying an image on a display of a mobile terminal. Especially, with the spread of contents such as an electronic book, wherein a user will read characters on a display of a mobile terminal for a longer time, a technology for providing a high visibility and reducing eye fatigue is important.
As described above, using an AMOLED, visibility decreases when an image is displayed darkly in order simply to reduce current consumption, while current consumption increases when an image is displayed brightly in order to increase visibility. Also, when using an LCD, when ambient light is brighter than the lightness of a display of a mobile terminal, visibility is lowered due to the limitation of the lightness of a backlight being is used as a light source.
Therefore, in order to display an image on a display of a mobile terminal, it is important to appropriately balance current consumption and visibility. In addition, because mobile terminals are equipped with different types of displays, such as an LCD, an AMOLED, etc., depending on products, and may be used in various environments, it is also important to develop a method for displaying an image to be suitable for a given ambient light and display type. For example, depending on whether a mobile terminal is used is inside or outdoors, the optimal visibility suitable for the different environments should be provided to the user. In addition, while visibility is important in displaying character-centered information content, such as an electronic book, eye fatigue is also an important factor for a user, when the user will read the character-center information content for a long time.